When designing devices such as field programmable gate arrays (FPGAs) on silicon, modeling is often performed to determine the properties and characteristics of materials and components on the silicon for performance purposes. Among the properties and characteristics that are modeled, temperature is one which requires special consideration as it impacts the performance and operability of components. As process technology has moved to and beyond 45 nm, the impact of temperature has only increased.
Pulse current measurement techniques have been used in the past to perform temperature readings on a silicon device. Measurement using pulses on a nanosecond time scale eliminates self-heating which had previously affected static measurements of silicon-on-insulator (SOI) metal oxide semiconductor field effect transistors (MOSFETs). Elimination of self-heating during measurement required that the measurements be made on a short time scale, and that there be a long relaxation time between measurements. The output characteristics of 0.2 μm partially depleted SOI transistors measured by this technique reproduced the kink effect, and represented the true output conductance and transconductance.
In order to utilize pulse current measurement techniques, an elaborate measurement system was needed. For example, a pulse generator was used to apply short voltage pulses to the device. An oscilloscope was also used to measure currents. The pulse current measurement techniques provided limited information regarding temperatures at multiple locations on a silicon device.